Helmbold



March 10, 1964 r. HELMBOLD TRANSVERSE FLOW TYPE BLOWERS 2 Sheets-Sheet 1 Filed April 5, 1961 INVENTOR Theodor Helmbold ATTOZNEYS March 10, 1964 T. HELMBOLD 3,124,301

TRANSVERSE FLOW TYPE BLOWERS Filed April 5, 1961 2 Sheets-Sheet 2 INVENTOR Theodor Helmbold pwwdw ATTORNEYS United States Patent 3,124,391 TRANSVERSE FLGW TYPE BLOWERS Theodor Hehnbolrl, Hedwigstrasse 4, Munich 2, Germany Filed Apr. 5, 1961, Ser. No. 101,014 Claims priority, application Germany Apr. 25, 1960 9 Claims. (Cl. 230125) The present invention relates to transverse flow type blowers of the type which incorporate a drum-shaped rotor and flow guiding body arranged within the interior of the rotor.

This is a continuation-in-part of my copending application Serial No. 96,953 filed March 20, 1961, and entitled Transverse Flow Type Blowers.

Transverse flow type blowers have previously been suggested which have a drum-shaped rotor and multi-shaped stationary bodies disposed within the rotor. These multishaped stationary bodies function to guide fluid flow within the rotor. While these stationary guiding bodies favorably influence the airstream in the interior of the blower rotor, they cause additional frictional resistance for the streaming medium.

With transverse flow type blowers of the kind disclosed in said copending application, a vortex is formed within the blower rotor radially opposite from a blower housing partition disposed exteriorly of the rotor and separating rotor fluid inlet channel from the rotor fluid outlet channel. This vortex provides for the efficient operation of the blower as disclosed in said copending application.

A disadvantage of transverse flow blowers of the type described above it that the distribution of fluid flow through the outlet channel is not uniform. As a result, the available cross-sectional flow area of the outlet channel is not efiiciently utilized and, under certain conditions, a reverse flow may even take place, particularly when working against a higher pressure.

The object of this invention is to avoid the foregoing disadvantage. This is accomplished in accordance with the present invention by rotatably arranging a freely driven cylindrical flow guiding body within the interior of the drum-shaped blower rotor at a position which is opposite to the exterior supporting body and between inlet and outlet of the blower.

In this manner, the fluid stream passing through the blower does not develop whirls in the boundary layer around the periphery of the blower rotor and adjacent to the surface of the flow guiding body as arises with stationary guiding bodies. As a result of eliminating the whirls in the foregoing fluid boundary layer, it will be appreciated that the efiiciency of the blower is improved.

In accordance with the present invention, the cylindrical flow guiding body may be conveniently provided with blades arranged around the periphery of the body and extending radially and essentially parallel in axis to said body.

According to a further feature of this invention, instead of the rotatable cylindrical flow guiding body with its blade arrangement, there is provided a drum-shaped driven body constructed in the same manner as a transverse flow type blower rotor. This driven drum-shaped body is driven in a closed path around the rotational axis of the blower rotor either in the same direction as the blower rotor or in a direction opposite thereto. The drum-shaped body is rotated in a direction which is opposite to that of the blower rotor and guides the flow of fluid passing through the blower rotor. With this blower construction, the fluid stream is guided to a certain degree around the driven drum-shaped body so that especially at the outlet side of the transverse flow type blower, a considerably improved distribution of the supplied medium ice over the cross section of the outlet is attained. By this favorable flow distribution within the cross section of the outlet an appreciable increase of the efliciency of the blower is etfectuated and, in addition, the intensity level of the noise produced by the blower is reduced.

The cylindrical guiding body according to one embodiment of the invention may be supported to be freely rotatable so that it starts to rotate as soon as fluid begins to flow along the guiding body. The cylindrical guiding body, however, additionally may be driven by a separate external power source in the corresponding turning diection. The amount of power required to rotate the guiding body, however, is relatively very small. On the other hand, the resultant improvement which the guiding body has on the efiiciency of the blower is considerably increased.

In order to arrange the cylindrical guiding body in a position most favorable with regard to the working conditions of the transverse flow type blower, the guiding body may be adjustably arranged axially parallel to the axis of the blower rotor. The drive for the cylindrical guiding body may advantageously include an infinitely variable V-belt drive, a frictional wheel gear or the like, whereby a variation of the speed ratio of the blower rotor relative to the cylindrical guiding body is attainable.

In addition, the cylindrical guiding body, especially at its side adjacent to the axis of the blower rotor, may be covered partially by an arcuate member mounted outside of the guiding body.

By mounting the rotatable cylindrical guiding body within the interior of the transverse flow type blower according to the invention, the fluid stream passing through the blower rotor is distributed uniformly over the cross sectional area of the fluid outlet channel. It the blower is supplying fluid against increased pressure within the outlet channel, this arrangement according to the inven tion avoids a back flow of the supplied medium.

This construction of the body enables the fluid stream to pass through the body and additionally to be acceler ated.

Some embodiments of a transverse flow type blower illustrating and operable upon the foregoing principles will now be described with reference to the accompanying drawings in which like parts have been designated by like reference numerals with differing letter suflixes and in which:

FIGURE 1 shows one embodiment of transverse flow type blower according to the present invention;

FIGURE 2 shows another embodiment of the transverse flow type blower;

FIGURE 3 shows a further embodiment of a transverse flow type blower according to the present invention;

FIGURE 30*. is a section taken along lines 3a-3a of FIGURE 3; and

FIGURE 4 is a section taken along lines 4-4 of FIG- URE 3a.

Referring now to FIGURE 1 of the drawings, the supplied medium is drawn by a rotor 1 through a suction opening 2 and flows through the rotor towards an outlet opening 3. A partition between the inlet and outlet sides is formed by a stationary member 4 arranged within the blower housing but externally of blower rotor 1. In the interior of blower rotor 1 there is arranged a cylindrical flow guiding body '5. Body 5 is mounted for rotation about an axis extending parallel to the rotational axis of blower rotor 1. As shown in FIGURE 1, body 5 is located at the side of blower rotor 1 which is diametrically opposite to member 4 such that the rotational axis of blower rotor 31 is between member 4 and the rotational axis of body 5. Body 5 is rotated in the opposite direction with respect to the direction of rotation of blower rotor 1 by the fluid stream which passes through the blower, or by means of a frictional gear (not shown) driven by an external power source.

In operation of the blower illustrated in FIGURE 1, the fluid medium enters rotor 1 through channel 2. In the region of the outer partition 4, a vortex or potential whirl indicated at A is formed inside the rotor and is generally disposed radially between the axis of the rotor rotation and partition 4 as shown. A trough-shaped guide body 20 may be employed to support vortex A as fully disclosed in said copending application.

Without the provision of the guiding body according to the present invention, it has been observed that fluid flow entering outlet 3 in the vicinity of partition 4 is greater than on the opposite side of outlet 3.

In accordance with the present invention, however, the rotating body '5 draws the fiow in the manner shown by the arrows and causes an increased flow in the region indicated at B which is within outlet 3 on the side thereof opposite from partition 4. As a result, it is clear that the distribution of flow through outlet 3 becomes more uniform to provide for a more eflicient utilization of the available cross sectional flow area provided by outlet 3.

FIGURE 2 shows a transverse flow type blower with a rotor 1a. Within the interior of blower rotor la there is provided a rotatable cylindrical body 5a which is disposed diametrically opposite to the partition body 40 between the inlet 2a and the outlet 3a. Body 5a is provided with a plurality of essentially equiangularly spaced straight blades 6a which extend radially from its outer periphery.

In the embodiment of FIGURE 2, body 5a is rotatably driven by a gear (not shown) in the same direction as that of blower rotor 1a. The body 5a is partially covered by a member 7a at its side adjacent to the rotational axis of the blower rotor.

With continued reference to FIGURE 2, it is clear that member 7a is rigidly fixed in place relative to the blower housing and extends with a uniform running clearance radially outwardly of the body blades between the rotational axes of body 5a and blower rotor 1:: respectively. Member 7a is formed and mounted such that its radius of curvature is coincident with the rotational axis of body 5a. I

In operation of the blower illustrated in FIGURE 2, the vortex A is formed, as previously mentioned as fluid flows through rotor la from inlet 2a. lades 6a aid in directing fluid toward region Ba to thus increase an otherwise weak flow in this vicinity. Covering member 7a guides the movement of fluid in the vicinity of blade 61! to prevent the movement imparted by blades 6a from interfering with the transverse flow of fluid through the central region of rotor la.

FIGURE 3 shows a transverse flow type blower disposed within the interior of rotor 1b. This transverse flow type blower comprises a rotatable body 81) positioned adjacent to the periphery of rotor ll; and diametrically opposite from the partition body 4b. Body 81) is drumshaped and at its outer periphery, it is provided with a plurality of parallel curved blades extending generally radially outwardly of the outer periphery of body 812. The body 8b is rotatably mounted on a rigid link 9b which is pivoted about the rotational axis of the blower rotor 7b. By this construction, it is clear that body 8b is selectively revolved in either direction in a closed path concentrically and coaxially around the rotational axis of blower rotor 1b. At the same time, body 812 is rotatable, in the manner herein before described, about its own rotational axis in a direction opposite to that of blower rotor lib.

Thus, it is apparent from FIGURES 3 and 3a that body 8b is mounted for pivotal movement about the rotor rotational axis by means of links 912 which are journalled on a rotor shaft 29 mounting rotor 16.

Body Sb preferably is rotatably supported between links 9!) as shown in FIGURE 3a to assure adequate structural support for body 8b if needed. It will be appreciated,

however, that any suitable structure may be employed to rockably mount body 817 for pivotal movement about the rotor rotational axis.

By rockably mounting body 812 in this manner, it is clear that body 812 is adjustable to a position providing the most efficient blower operation to meet different conditions such as variations in delivery requirements.

With reference to FIGURES 3a and 4, body 8b is mounted on a shaft 33 extending through an arcuate slot 32 formed in the blower housing which is designated by the reference numeral 34. Shaft 34 is preferably parallel to the rotor shaft 29 mounting rotor 1b. Shaft 2? is driven by any suitable means such as a motor 38 which is drive connected to shaft 29 by a conventional pulley and belt drive assembly 40. Shaft 36 is drive connected to motor 38 by a conventional infinitely variable V-belt drive indicated at 42. Such a V-belt drive is disclosed in United States Letters Patent No. 2,695,529 issued to L. R. Evans on November 30, 1954. It will be appreciated that the rotation of shaft 36 relative to shaft 29 may be easily changed by crossing 0r uncrossing one of the belts in belt drive 42.

Any suitable means may be utilized to fix shaft 30 in its adjusted position such as, for example, a nut and bolt assembly 44 (FIGURE 3) mounted in an arcuate housing slot 43 and fixing at least one of the links 9b to housing 34.

In operation of the blower illustrated in FIGURES 3 and 3a, body 8b will direct an increased amount of fluid to a region indicated at Bb (FIGURE 3) within outlet 317 at the side thereof opposite from partition 4b. Thus, by positioning body 812 as explained above, the amount of fluid diverted thereby can be controlled.

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

What is claimed and desired to be secured by United States Letters Patent is:

l. A transverse flow type blower comprising a rotatable bladed drum-shaped blower rotor, means including a partition providing a rotor fluid inlet and a rotor fluid outlet with said rotor being disposed between said inlet and said outlet and rotatable in a predetermined direction to convey fluid from said inlet to said outlet, said partition being disposed externally adjacent to said rotor between said inlet and said outlet, and an essentially cylindrical flow guiding body rotatably mounted Within said rotor eccentrically of .the rotational axis of said rotor and on the side thereof opposite from said partition for directing a portion of the fluid passing through said rotor to a predetermined region in said outlet.

'2. The blower according to claim 1 wherein said cylindrical fiow guiding body is arranged axially parallel to the rotor and is provided at its periphery with blades extending radially therefrom.

3. The blower defined in claim 2 comprising a covering member disposed adjacent said blades and extending between the rotational axis of said rotor and said guiding body.

4. The blower according to claim 1 wherein said flow guiding body is constructed in the form of a drum-shaped blower rotor.

5. The blower according to claim 1 comprising means mounting said body for pivotal movement about the rota tional axis of the blower rotor.

6. The blower according to claim 1, wherein said flow guiding body is provided with a drive adapted to rotate said flow guiding body in opposite directions relative to said blower rotor.

7. The blower according to claim 6 comprising means for changing the speed ratio between the blower rotor and said body. 5

8. The blower defined in claim 1 wherein said guiding body is freely rotatable about an axis parallel to the rotational axis of said rotor and is adapted to be driven by flow of fluid through said rotor.

9. The blower according to claim 8 comprising me- 10 chanical power means for imparting a drive force to said body.

References Cited in the file of this patent UNITED STATES PATENTS 2,658,700 Howell Nov. 10, 1953 FOREIGN PATENTS 559,024 Belgium Jan. 6, 1958 

1. A TRANSVERSE FLOW TYPE BLOWER COMPRISING A ROTATABLE BLADE DRUM-SHAPED BLOWER ROTOR, MEANS INCLUDING A PARTITION PROVIDING A ROTOR FLUID INLET AND A ROTOR FLUID OUTLET WITH SAID ROTOR BEING DISPOSED BETWEEN SAID INLET AND SAID OUTLET AND ROTATABLE IN A PREDETERMINED DIRECTION TO CONVEY FLUID FROM SAID INLET TO SAID OUTLET, SAID PARTITION BEING DISPOSED EXTERNALLY ADJACENT TO SAID ROTOR BETWEEN SAID INLET AND SAID OUTLET, AND AN ESSENTIALLY CYLINDRICAL FLOW GUIDING BODY ROTATABLY MOUNTED WITHIN SAID ROTOR ECCENTRICALLY OF THE ROTATIONAL AXIS OF SAID ROTOR AND ON THE SIDE THEREOF OPPOSITE FROM SAID PARTITION FOR DIRECTING A PORTION OF THE FLUID PASSING THROUGH SAID ROTOR TO A PREDETERMINED REGION IN SAID OUTLET. 